Collapse sensing check valve

ABSTRACT

A method and apparatus for a pressure relief valve assembly. The valve assembly may be coupled to one or more casings and/or tubular members to control fluid communication therebetween. The valve assembly is a one-way valve assembly that relieves pressure within an annulus formed between adjacent casings and/or tubular members to prevent burst or collapse of the casings and/or tubular members. The valve assembly is resettable downhole.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of U.S. Provisional Patent ApplicationSer. No. 61/481,088, filed Apr. 29, 2011, which is herein incorporatedin its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the invention generally relate to a pressure relief valveassembly.

2. Description of the Related Art

Traditional well construction, such as the drilling of an oil or gaswell, includes a wellbore or borehole being drilled through a series offormations. Each formation, through which the well passes, must besealed so as to avoid an undesirable passage of formation fluids, gasesor materials out of the formation and into the borehole. Conventionalwell architecture includes cementing casings in the borehole to isolateor seal each formation. The casings prevent the collapse of the boreholewall and prevent the undesired inflow of fluids from the formation intothe borehole.

In standard practice, each succeeding casing placed in the wellbore hasan outside diameter significantly reduced in size when compared to thecasing previously installed. The borehole is drilled in intervalswhereby a casing, which is to be installed in a lower borehole interval,is lowered through a previously installed casing of an upper boreholeinterval and then cemented in the borehole. The purpose of the cementaround the casing is to fix the casing in the well and to seal theborehole around the casing in order to prevent vertical flow of fluidalongside the casing towards other formation layers or even to theearth's surface.

If the cement seal is breached, due to high pressure in the formationsand/or poor bonding in the cement for example, fluids (liquids or gases)may begin to migrate up the borehole. The fluids may flow into theannuli between previously installed casings and cause undesirablepressure differentials across the casings. The fluids may also flow intothe annuli between the casings and other drilling or production tubularmembers that are disposed in the borehole. Some of the casings and othertubulars, such as the larger diameter casings, may not be rated tohandle the unexpected pressure increases, which can result in thecollapse or burst of a casing or tubular.

Therefore, there is a need for apparatus and methods to prevent wellborecasing and tubular failure due to unexpected downhole pressure changes.

SUMMARY OF THE INVENTION

In one embodiment, a valve assembly comprises a tubular mandrel; asleeve member disposed within the tubular mandrel; and a biasing memberdisposed within the tubular mandrel and operable to bias the sleevemember against a shoulder of the tubular mandrel. The sleeve member ismovable between a closed position where fluid communication is closedbetween a bore of the valve assembly and a port disposed through thetubular mandrel, and an open position where fluid communication is openbetween the bore of the valve assembly and the port disposed through thetubular mandrel.

In one embodiment, a method of controlling fluid communication betweenan exterior of a wellbore tubular and an interior of the wellboretubular comprises providing a valve assembly for coupling to thewellbore tubular, wherein the valve assembly includes a tubular mandrel,a sleeve member movably disposed in the tubular mandrel, and a biasingmember for biasing the sleeve member into a closed position; and movingthe sleeve member to an open position to open fluid communicationbetween the exterior of the wellbore tubular and the interior of thewellbore in response to a pressure differential exceeding a firstpredetermined value.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the inventioncan be understood in detail, a more particular description of theinvention, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlytypical embodiments of this invention and are therefore not to beconsidered limiting of its scope, for the invention may admit to otherequally effective embodiments.

FIG. 1 is a schematic view of a wellbore.

FIG. 2 is a cross sectional view of a valve assembly in a closedposition.

FIG. 3 is a cross sectional view of the valve assembly in an openposition.

DETAILED DESCRIPTION

FIG. 1 illustrates a wellbore 5 formed within an earthen formation 80.The walls of the wellbore 5 are reinforced with a plurality of casings10, 20, 30 of varying diameters that are structurally supported withinthe formation 80. The casings 10, 20, 30 are fixed within the formation80 using a sealing material 15, 25, 35, such as cement, which preventsthe migration of fluids from the formation 80 into the annuli betweenthe casings 10, 20, 30. One or more tubular members 40, 45, such asdrilling or production tubular members, may also be disposed in thewellbore 5 for conducting wellbore operations. An annulus “A” is formedbetween the casing 10 and the casing 20, and an annulus “B” is formedbetween the casing 20 and the tubular member 40. It is important to notethat the embodiments described herein may be used with other wellborearrangements and are not limited to use with the wellbore configurationillustrated in FIG. 1.

The wellbore 5 may intersect a high pressure zone 50 within theformation 80. Fluids within the high pressure zone 50 are sealed fromthe annulus A and B by the sealing material 25 that is disposed betweenthe casing 20 and the wellbore 5 wall. In the event that the sealingmaterial 25 is breached or otherwise compromised, pressurized fluids maymigrate upward into the annulus A and cause an unexpected pressureincrease. The pressure rise may form a pressure differential across thecasings 10, 20 that (if unchecked) may result leakage through or burstof casing 10, and/or leakage through or collapse of the casing 20. Avalve assembly 100 is provided to relieve the pressure in the annulus Aprior to failure of one or both of the casings 10, 20.

FIG. 2 illustrates the valve assembly 100 in a closed position. Thevalve assembly 100 is shown coupled to the casing 20 in FIG. 1, but eachof the casings 10, 20, 30 and/or the tubular members 40, 45 maysimilarly include one or more of the valve assembly 100 as describedherein. The valve assembly 100 may be coupled to the casings 10, 20, 30and/or the tubular members 40, 45 using a threaded connection, a weldedconnection, and/or other similar connection arrangements.

The valve assembly 100 may comprise a top sub 110, a bottom sub 120, asleeve member 130, and a biasing member 140. The bottom sub 120 iscoupled to the top sub 110, such as by a threaded connection. In oneembodiment, the top sub 110 and the bottom sub 120 may be integrallyformed as a single tubular mandrel. The sleeve member 130 is movablydisposed within the top sub 110, and may be biased against a shoulder125 or upper end of the bottom sub 120 by the biasing member 140. Thebiasing member 140 may be a spring or other similar biasing mechanism.The biasing member 140 is also disposed within the top sub 110, and maybe positioned between the sleeve member 130 and a shoulder 113 of thetop sub 110. A cover member 145 optionally may be provided to secure thebiasing member 140 within the top sub 110 and to protect the biasingmember 140 from interference with any component(s) that pass through thebore 105 of the valve assembly 100. The inner diameters of the top sub110, the bottom sub 120, the sleeve member 130, and/or the cover member145 may be equal to provide a substantially uniform inner diametersurface throughout the length of the valve assembly 100. In oneembodiment, the inner diameter of the bore 105 of the valve assembly 100(including the top sub 110, the bottom sub 120, and/or the sleeve member130) may be substantially equal to or greater than the inner diameter ofthe casings 10, 20, 30 and/or the tubular members 40, 45 to which it isattached when assembled.

As illustrated in FIG. 2, the sleeve member 130 is biased into theclosed position. When in the closed position, sealing members 131, 132,133, such as o-rings, close fluid communication between the bore 105 ofthe valve assembly 100 and the annulus surrounding the valve assembly100. In particular, the sealing members 131, 132, 133 seal fluidcommunication to a first port 115 and a second port 117 that aredisposed through the body of the top sub 110. The first port 115 issealed on opposite sides by sealing members 131 and 132. The second port117 is sealed on opposite sides by sealing members 132 and 133.

An external piston area 139, such as a shoulder portion, is provided onthe sleeve member 130 between sealing members 132 and 133 and is influid communication with the second port 117. An internal piston area135 is formed by an end of the sleeve member 130, which is in contactwith the biasing member 140 and is in fluid communication with the bore105 of the valve assembly 100. When the force on the internal pistonarea 135 is greater than the force on the external piston area 139, thevalve assembly 100 is moved to the closed position as shown in FIG. 2.When the force on the external piston area 139 is greater than the forceon the internal piston area 135, the valve assembly 100 is moved to theopen position as shown in FIG. 3.

In an optional embodiment, the sleeve member 130 may be initiallycoupled to the top sub 110 and/or the bottom sub 120 by one or moreshearable members, such as shear pins 137 illustrated in FIG. 2. Theshear pins 137 may retain the sleeve member 130 in a closed position toprevent inadvertent actuation of the sleeve member 130 by acomponent(s), such as a drilling or production string, that is movedthrough the bore 105 of the valve assembly 100 during a wellboreoperation. The shear pins 137 may be sheared by pressurizing the annulussurrounding the valve assembly 100 to force the sleeve member 130 intothe open position as described herein. The force required to shear theshear pins 137 may be greater than the force required to subsequentlymove the sleeve member 130 to the open position. In one embodiment, atool or other downhole device may be lowered into the bore 105 of thevalve assembly 100 and into engagement with the sleeve member 130 toapply a force sufficient to shear the shear pins 137.

FIG. 3 illustrates the valve assembly 100 in the open position, wherethe bore 105 of the valve assembly 100 is in fluid communication withthe annulus surrounding the valve assembly 100 via the first port 115.The pressure in the annulus surrounding the valve assembly 100 maygenerate a force on the external piston area 139 sufficient to overcomethe force on the internal piston area 135. The force on the internalpiston area 135 may include the force from the biasing member 140, suchas a spring force, plus the force generated by any pressure within thebore 105 acting on the internal piston area 135. The force on theexternal piston area 139 may move the sleeve member 130 to a positionsuch that the first port 115 is open to fluid communication with thebore 105 of the valve assembly 100. In particular, the sealing member131 is moved across the first port 115 to open fluid communication.

Referring back to FIG. 1, the valve assembly 100 may be operable tocontrol fluid communication between the annulus A and the annulus B. Theannulus A surrounds the valve assembly 100, and the annulus B is influid communication with the bore 105 of the valve assembly 100.Pressure in the annulus A may act on the external piston area 139 viathe second port 117 to move the sleeve member 130 against the force ofthe biasing member 140 and any pressure force in the annulus B acting onthe internal piston area 135. When the valve assembly 100 is open,pressurized fluid may flow from the annulus A to the annulus B throughthe first port 115 of the valve assembly 100. The valve assembly 100 isthus operable to relieve a pressure that may cause burst of a casingexterior to the casing to which the valve assembly 100 is attached,and/or collapse of a casing to which the valve assembly 100 is attached.

When the pressure in the annulus A and the force acting on the externalpiston area 139 decreases to a predetermined amount, the biasing member140 may move the sleeve member 130 back to the closed position where thesealing members 131, 132 close fluid communication to the first port115. In this manner, the valve assembly 100 is operable as a one-wayvalve in that it will permit fluid flow into the bore 105 of the valveassembly 100 but will prevent fluid flow out of the bore 105 via thefirst port 115. The valve assembly 100 is automatically resettabledownhole and may be operated multiple times in response to any pressurefluctuations within the wellbore 5. As stated above, any of the casings10, 20, 30 and/or the tubular members 40, 45 may each be provided withone or more valve assemblies 100 to allow fluid flow from a surroundingcasing or tubular member to an inner casing or tubular member, whilepreventing fluid flow in the opposite direction. The valve assembly 100vents off collapse pressure from the outside of the casings 10, 20, 30and/or tubular members 40, 45 but allows internal pressurization of thecasings 10, 20, 30 and/or tubular members 40, 45. The internal pressureholding integrity of the casings 10, 20, 30 and/or tubular members 40,45 is provided by the seal formed between the top sub 110 and the sleevemember 130 with the sealing members 131, 133.

In one embodiment, a casing 10, 20, 30 and/or tubular member 40, 45 maybe provided with multiple valve assemblies 100 that are spaced apartalong the length of the casing or tubular member. The valve assemblies100 may be operable to open and/or close at different pre-determinedpressure setting. One or more of the valve assemblies 100 may beoperable to open when a first predetermined pressure acts on theexternal piston area 139, while one or more of the other valveassemblies 100 may be operable to open when a second predeterminedpressure acts on the external piston area 139. The first predeterminedpressure may be greater than, less than, or equal to the secondpredetermined pressure.

In one embodiment, the valve assembly 100 may be operable to open when apressure differential across the valve assembly 100 exceeds a firstpredetermined value. The valve assembly 100 may be operable to closewhen the pressure differential across the valve assembly 100 decreasesbelow a second predetermined value. The first predetermined value may begreater than or equal to the second predetermined value. For example,the valve assembly 100 may include a detent mechanism and/or a colletassembly configured to retain the valve assembly 100 in the openposition until the pressure differential across the valve assembly 100decreases below the second predetermined value. In one embodiment, thedetent mechanism may include a c-ring coupled to the sleeve member 130that engages a shoulder of the top sub 110. When moved to the openposition, the sleeve member 130 may move the c-ring across the shoulderwith minimal resistance, but when moved to the closed position, thesleeve member 130 may encounter a greater resistance to move the c-ringacross the shoulder. Other detent arrangements may be use with theembodiments described herein.

While the foregoing is directed to embodiments of the invention, otherand further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

1. A valve assembly, comprising: a tubular mandrel; a sleeve memberdisposed within the tubular mandrel; and a biasing member disposedwithin the tubular mandrel and operable to bias the sleeve memberagainst a shoulder of the tubular mandrel, wherein the sleeve member ismovable between a closed position where fluid communication is closedbetween a bore of the valve assembly and a port disposed through thetubular mandrel and an open position where fluid communication is openbetween the bore of the valve assembly and the port disposed through thetubular mandrel.
 2. The valve assembly of claim 1, further comprising aseal member for sealing the port from communication with the bore whenthe sleeve member is in the closed position.
 3. The valve assembly ofclaim 2, wherein the seal member is coupled to the sleeve member and ismovable across the port to open fluid communication.
 4. The valveassembly of claim 1, further comprising an internal piston area and anexternal piston area, wherein the biasing member contacts the internalpiston area, and wherein the external piston area is in fluidcommunication with an annulus surrounding the valve assembly.
 5. Thevalve assembly of claim 4, wherein the internal piston area is formed byan end of the sleeve member, and wherein the external piston area isformed by a shoulder of the sleeve member.
 6. The valve assembly ofclaim 5, wherein the external piston area is in fluid communication withthe annulus via a second port disposed through the tubular mandrel. 7.The valve assembly of claim 6, further comprising a seal member forsealing communication between the second port and the bore.
 8. A methodof controlling fluid communication between an exterior of a wellboretubular and an interior of the wellbore tubular, comprising: providing avalve assembly for coupling to the wellbore tubular, wherein the valveassembly includes a tubular mandrel, a sleeve member movably disposed inthe tubular mandrel, and a biasing member for biasing the sleeve memberinto a closed position; and moving the sleeve member to an open positionto open fluid communication between the exterior of the wellbore tubularand the interior of the wellbore in response to a pressure differentialexceeding a first predetermined value.
 9. The method of claim 8, furthercomprising moving the sleeve member to the closed position using thebiasing member to close fluid communication between the exterior of thewellbore tubular and the interior of the wellbore tubular.
 10. Themethod of claim 9, further comprising controlling fluid flow through aport in the tubular mandrel using the sleeve member.